Tsvangirai postpones Zimbabwe return after threat

Sibotshiwe said party officials would consult their own security experts and regional leaders for advice. He said Tsvangirai would return "at the earliest opportunity."

Tsvangirai has survived three assassination attempts, including one in 1997 by unidentified assailants who tried to throw him from a 10th floor office window. Last year, he was hospitalized after a brutal assault by police at a prayer rally, and images seen around the world of his bruised and swollen face have come to symbolize the plight of dissenters in Zimbabwe.

Tsvangirai's Movement for Democratic Change says that more than 30 of its supporters and activists have been killed since the first round of voting March 29, and that attacks are increasingly targeting its top leaders.

Tsvangirai won the first round, but, according to official results, fell short of an outright majority.

Tsvangirai claims he won the first round outright, but nonetheless agreed to take part in a runoff after the official results were announced May 2. He said, though, that the runoff should be held within three weeks of the announcement of results, as Zimbabwean law stipulates.

Instead, Zimbabwe electoral officials announced Friday the runoff would be June 27, eight weeks after the results were announced, prompting concern that Mugabe's force would use the time to orchestrate more attacks on opposition supporters.

Sibotshiwe said that despite escalating violence, the late runoff date and now the assassination threat, Tsvangirai would take part in the runoff.

"Withdrawing from the runoff would not assist the Zimbabwean people in the short or long term," he said. "Withdrawing from the runoff would only hand power to Robert Mugabe."

At a ruling party central committee meeting Friday, Mugabe said ZANU-PF must work hard for victory to "repair the damage" suffered March 29.

He said the opposition was backed by "a hostile axis of powerful foreign governments" and global corporate enterprises looking to promote their own interests in Zimbabwe.